The Wood Frog That Freezes Solid
The impossible claim This frog freezes solid every winter — no breathing, no heartbeat, up to 70% of its body turned to ice — then thaws back to life in spring. The verified facts The wood frog (Lithobates sylvaticus) survives Alaskan winters by letting itself freeze. Its liver floods its blood with glucose and urea — natural cryoprotectants that protect cells while ice fills the spaces between them. Its heart stops, brain activity flatlines, and up to ~70% of body water turns to ice for up to seven months. ...